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<script>
    //或的练习
    let a = [1, 2, 3, 4, 5];//模拟购物车数据---起始的数据
    let b = '123';//模拟本地存储的数据----本地存储的数据
    let c = b || a;
    console.log(c);
</script>
<script>
      //举例子:或----并联     且与----串联
      let a = 0 ;
      let b = 6;
      let c = 100;
      console.log(a||b||c);
</script>
